Symptoms
The Microsoft Host Integration Server 2010 SNA Server service may not process messages correctly when many clients constantly request Advanced Program-to-Program Communications (APPC) sessions while the server is starting. This causes the clients to be unable to establish APPC sessions even after all Host Integration Server services are up and running.
Cause
This problem occurs because the client's session request control block may be cleaned up two times under these conditions.
Resolution
Cumulative update information
The fix that resolves this problem is included in cumulative update package 8 for Host Integration Server 2010. For more information about how to obtain the cumulative update package, see Cumulative update package 8 for Host Integration Server 2010.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More Information
When the SNA Server service is starting, not all dependent services such as a link service are fully running. This causes client session requests to be queued and not processed by the SNA Server service.
A client's session request may time out before the services are fully running. Therefore, the client's session request control block is cleaned up.
When the SNA Server service is fully running and the Links service is starting, the queued messages are processed by the SNA Server service. If the Links service is not yet up and running, the request fails, and the SNA Server service returns an error message to the client. However, the client's control block is already cleaned up, and this leads to the problem that is mentioned in the "Symptoms" section.
